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Formatted & Logical Faults · case file

It Shows as Connected, but I Can't Open the Files

She is "unable to access photos on my external hard drive", a drive that had held them without trouble for years. It "shows as connected to laptop, but I cannot open the files", and the trouble started when she went to add more. A drive that connects but will not open anything has a broken index, not broken hardware. The mechanism is turning, the computer can see it, and the photographs are sitting exactly where they always were — but the map that says which sector belongs to which picture has come apart, so nothing can be found. That is a filing failure, and the timing tells you why: writing to a drive is when the map gets edited, and an edit interrupted halfway leaves it in pieces.

External DriveCorruption / Filesystem
// case at a glance
MediaAn external hard drive holding several years of family photographs, connecting normally but unable to open any of them.
Reported situationExternal hard drive · years of photographs stored without incident · shows as connected to the laptop · files will not open · problem began while adding more photographs.
Fault classFilesystem fault — the drive powers, is detected and responds, but the structures describing where each file lives have been damaged, most likely by an interrupted write. Photographs intact; further writing to the drive is the risk.
Equipment usedRead behind a hardware write-blocker in line so that nothing further could be written · imaged out to DeepSpar with PC-3000 UDMA behind it · the filesystem read out in R-Studio from the image and the damaged structures rebuilt · anything whose references had gone recovered by content signature, then every photograph checked by rendering before it went to fresh media.
// the decode

The decode

A hard drive keeps two quite separate things: your photographs, and a set of tables saying where each of them begins and ends. Damage the tables and the drive behaves exactly as this one does — present, powered, listed by the computer, and completely unable to hand anything over. The pictures have not gone anywhere. The catalogue describing them has.

The timing points straight at the cause. Adding files is one of the few moments a drive rewrites those tables, and if that rewrite is interrupted — a cable nudged, a laptop that sleeps, a drive that stalls for a second — the structures can be left half-updated and internally contradictory. Which is how a drive that behaved impeccably for four years becomes unreadable during a five-minute copy, and why the fault feels so unfair to the person it happens to.

The repair is not done on the drive, and that distinction matters more than anything else here. Every tool Windows or macOS offers at this point writes to the disk while attempting to fix it, and each write lands on the very structures a recovery would otherwise reconstruct. So the drive is imaged read-only first, and the rebuilding happens on that image, where a wrong turn costs nothing. Where references have gone entirely, photographs are recovered by their own content instead — a JPEG or a raw file has a recognisable beginning, whatever the catalogue says.

// on the bench

On the bench

It went with a write-blocker sitting in front of it immediately, so that nothing on the drive could change while it was being looked at, and copied to an image on DeepSpar, PC-3000 UDMA underneath. The filesystem was read out in R-Studio from that image and the damaged structures rebuilt on the copy. Where references had been lost altogether, the photographs were carved out by content signature. Every one of them was rendered before it went onto fresh media, because a file that appears in a list and a file that opens are different claims.

// the outcome

The outcome

Imaged read-only, filesystem rebuilt from the copy, and the photographs put onto fresh media with the folder structure largely intact. The diagnostic cost nothing; the figure that followed was fixed, written and inclusive of VAT. The hardware was sound and the fault was logical, so this ran on no fix, no fee terms — had the pictures not come back, there would have been no charge. The drive itself was returned, working, with the strong recommendation that it stop being the only place those photographs live.

A drive that connects but will not open anything

Stop writing to it, and that includes letting the computer help. A drive that mounts but opens nothing has a damaged index rather than damaged hardware, and the repair tools built into Windows and macOS all work by writing corrections onto the disk — straight over the structures a recovery would rebuild from. Do not run chkdsk, do not run First Aid, do not accept an invitation to repair, and above all do not reformat, however confidently you are told it will help. Unplug it, leave it alone, and have it imaged first. Almost all of these come back complete; the ones that do not are usually the ones somebody tried to mend in place.

Something similar sitting on your desk? Every job on this site begins the same unhurried way: a diagnostic that costs nothing, done within 2 working days of the parcel landing on the bench, and then a single written figure that does not move afterwards. Logical faults carry no fix, no fee. Where a drive has to be opened, or its board rebuilt after impact, an electrical fault, water or fire, 50% of the quote falls due first and the rest only on success. Ransomware, CCTV recorders, BitLocker volumes and other forensic-classed jobs are settled in advance and in full. Where the data sits inside a laptop, a desktop, a Mac or a server, take the drive or SSD out and send that by itself: we do not remove internal drives from machines, and memory soldered onto a logic board (Apple Silicon Macs and the like) sits outside what we take. If it unplugs or unscrews, it is our sort of work. Post it tracked and insured to Cambridge Data Recovery, Compass House, Vision Park, Chivers Way, Cambridge CB24 9AD, use a courier you book and pay for yourself, or hand it over the desk there — there is no collection service. Packing advice and the shipping form live here.
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